As shown in FIGS. 4 and 5, a prior art rack comprises a top frame 40 and a bottom frame 41. The top frame 40 is provided with a retaining projection 43. The bottom frame 41 is provided with four legs, each receiving a fitting portion 42 of the top frame 40 which is provided with four support rods 44, each having a receiving hole 45 which is provided with an arresting edge 46. The top frame 40 is joined with the bottom frame 41 such that the four fitting portions 42 of the top frame 40 are fitted into the four receiving holes 45 of the bottom frame 41. The fitting portions 42 are located securely in the receiving holes 45 by the retaining projection 43 which is arrested by the arresting edge 46 of the receiving hole 45. The four support rods 44 of the bottom frame 41 are of a hollow construction and are rested on a surface.
The prior art rack described above is defective in design in that it is integrally made of a plastic material by injection molding and is therefore apt to slide easily by itself. In addition, the hollow support rods 44 of the bottom frame 41 are likely to be infested with the household pests.